1. Field of the Invention
The present invention relates to a plate-shaped battery and an electronic apparatus. In particular, the invention relates to a method of sealing an electrode lead line of a battery and applying a covering laminate film to a plate-shaped battery.
2. Background to the Invention
FIG. 1 is a perspective view of the outer appearance of a conventional thin plate-shaped battery which is charged with and discharges battery energy. Typical examples include for instance a nickel-cadmium battery, a nickel-hydrogen battery, a lithium ion battery or the like. FIG. 2 is a cross sectional view along the line A-Axe2x80x2 of the plate-shaped battery in FIG. 1. FIG. 3 is a cross sectional schematic view of a battery core.
In the figures, reference numeral 81 denotes a thin plate-shaped battery which is a battery formed in a thin shape such as a nickel-cadmium battery, a nickel-hydrogen battery, a lithium ion battery or the like; reference numerals 2, 3 respectively denote positive and negative electrode lead lines which are the input and output terminals of the plate-shaped battery 1; 2a, 3a denote positive and negative electrode terminals of an internal battery, respectively; 2aa, 3bb denote the sheet-shaped positive and negative electrodes of the internal battery, respectively; and 82 denotes a separator interposed between the sheet-shaped positive electrode 2aa and negative electrode 3bb. 
Reference numerals 5, 9 each denote a metallic foil comprised by a metallic material such as aluminum which covers the internal battery; 4, 6, 8, 10 each denote a polymer resin such as polyethylene, polypropylene, polyethylene terephthalate, which is adapted to increase the weak mechanical strength of the metallic foil and which covers the metallic foil in order to prevent direct damage to the metallic foil 5 from the exterior. 11 comprises an external sheet which is a single sheet which is applied to the resins 4, 6 on the top and bottom of the metallic foil 5 and which covers the battery interior of the plate-shaped battery 1; 12 is an external sheet which comprises a single sheet which is applied to the resins 8, 10 on the top and bottom of the metallic foil 9 and which covers the battery interior of the plate-shaped battery 1 in the same way. Depending on a method of manufacture, the external sheets 11, 12 can be formed in a single folded sheet; 7 denotes an adhesive material comprised of an insulating material such as resin which sandwiches the positive and negative electrode lead lines 2, 3, with the external sheet 11 and the external sheet 12 and which fixes the positive and negative electrode lead lines by sealing the terminal with heat fusion or welding.
As shown in FIG. 3, the sheet-shaped positive and negative electrodes 2aa, 3bb in the battery interior 81a of the plate-shaped battery are electrically connected respectively with the positive and negative terminals 2a, 3a. The sheet-shaped positive and negative electrodes 2aa, 3bb in the battery interior of the plate-shaped battery 81 are electrically connected respectively with the positive and negative terminals 2a, 3a and form the input and output terminals of the battery. As shown in FIG. 2, the peripheries of the battery lead lines 2, 3 (see FIG. 3) are covered by external sheets 11, 12 and sealed by heat fusion or welding using a separate resin from that forming the exterior sheet. The battery lead lines 2, 3 are comprised of a thin straight plate.
As shown in FIG. 3, the battery interior 81a is a laminate structure formed of the sheet-shaped positive and negative electrodes 2aa, 3bb with a separator 82 there between. The laminated structure is filled with an electrolytic solution and the battery interior is completely sealed with a covering film.
The operation of the conventional battery 81 is described below.
The positive and negative electrodes lead lines 2, 3 of the plate-shaped battery 1 mounted in an electronic apparatus are connected to an electronic apparatus which mounts electrical circuits comprised from various types of electrical components on a printed board. Thus a potential difference is generated with the electrical components and a current flows through both the electrode lead lines 2, 3.
In such a way, the conventional plate-shaped battery 81 which uses polymer resins 4, 6, 8, 10 such as polyethylene, polypropylene, polyethylene terephthalate or the like, is covered in external sheets 11, 12 comprised of aluminum foil, for example. The foil comprises three layers interposing metallic foils 5, 9 comprised of aluminum which has few pinholes and high flexibility. However, although the terminals of the electrode lead lines 2, 3 are sealed with the external sheets 11, 12, the peripheries of the electrode lead lines 2, 3 are sealed by welding using an adhesive material separate from the polymer resins 4, 6, 8, 10 which comprise the laminate film.
Since the conventional plate-shaped battery 81 is structured as discussed above, the metallic foils 5, 9 which are formed from a large surface area aluminum sheet in the aluminum laminated film which covers the plate-shaped battery 81 are not connected with the electrode of the plate-shaped battery 81 and thus have a floating electric potential. Since the electric potential fluctuates, the problem has arisen that the electrical circuit, which supplies the electrical energy of the battery, and the interior battery 81a, which forms the battery core stored in the laminate film, are not used as an electrical shield (magnetic shield, electrostatic shield).
The further problem has arisen that in spite of the fact that the polymers 4, 6, 8, 10 such as polyethylene, polypropylene, or polyethylene terephthalate has a dielectric constant, the external sheets 11, 12 comprised by an aluminum laminated film or the like which contains the polymers 4, 6, 8, 10 are not used as a single electric component such as a condenser or an antenna.
The conventional plate-shaped battery 81 has a sealed structure complicated by the fact that a separate sealing resin 7 to the laminated film must be provided. Since an adhesive material 7 solely employed as a sealing resin for the sealed section is used, sealing is difficult.
Since the electrode lead lines 2, 3 each comprise a thin straight plate, the adhesion of the electrode lead lines 2, 3 and the external sheets 11, 12 comprising the laminated film is weak and the problem has arisen that forward and backwards motion in the direction of electrode lead line detachment is facilitated.
The present invention is proposed to solve the above problems and has the object of providing a plate-shaped battery using a metallic foil such as aluminum in the laminated film as an electrical shield and antenna. A laminated film containing resin having a dielectric constant is used as an electrical component such as a condenser.
A further object of the present invention is to increase the mechanical strength of the external terminal and to electrically connect the external terminal at the same time as well as fixing the plate-shaped battery to an electronic apparatus in order to determine the capacity of the condenser.
The present invention has a simplified structure and a plate-shaped battery is proposed with improved adhesion in which the lead lines do not move forwards and backwards in a detaching direction.
The plate-shaped battery of the present invention is provided with a laminated film of laminated polymer resin and metallic foil which seals the positive and negative electrode terminals as well as covering the electrical core. The metallic foil is electrically connected with the positive and negative poles of the battery core.
The laminated film has conventionally not been used as an electrical component. However, with such a structure, it is possible to use the film as an electrical component having the same potential as the reference potential of the battery.
The plate-shaped battery of the present invention disposes a first aperture and a second aperture which respectively expose both terminals in a terminal section in which the positive and negative terminals are sealed by a laminated film. Either one of the first and second apertures is electrically connected with a metallic foil.
In such a way, an electrical circuit in an electronic apparatus such as a radio which stores a plate-shaped battery can be operated in a stable manner and the potential of the metallic foil in the laminated film is set to the same reference potential as that of the battery.
The plate-shaped battery of the present invention allows the extensions of the positive and the negative electrodes or other electrodes in order to provide a fixed potential in the metallic foil in the laminated film.
In this way, since the metal in the laminated film is extended outside the battery housing from a part of the laminated film and not from the battery core, the potential can be easily fixed.
The plate-shaped battery of the present invention provides a hole in a section of the battery housing. An electrode can be led through the open hole.
In such a way, it is possible to improve the mechanical strength of the laminate seal proximate to the terminal section.
According to the plate-shaped battery of the present invention, in the metallic foil inside the laminated film, either the positive terminal or the negative terminal and the positive or the negative pole outside the battery housing are positioned with respect to the lead line of the metallic foil in the same section or in different sections when observed from the top.
In such a way, since the metallic foil in the laminated film is connected with the terminal outside the housing, it is possible to perform a connection by adhesion, press fitting or welding in a stable manner and to thus improve adhesive strength.
The plate-shaped battery of the present invention comprises an electrical shield, magnetic shield or electrostatic shield which shields an electrical circuit, which supplies the electrical energy of the battery, and the battery core incorporated in the laminated film. The shield is comprised of electrically connecting the metallic foil in the laminated film to the negative and positive poles.
In such a way, since the metallic foil in the laminated film has the same equipotential as the electrode, the battery core and interior of the laminated film, and the electrical circuit which supplies the electrical energy of the battery may be electrically shielded (magnetically shielded. electrostatically shielded).
The plate-shaped battery of the present invention leads a metallic terminal, which is electrically connected with the metallic foil in the laminated film, from a section of the battery housing which is separate to the positive and negative electrodes.
In such a way, it is possible to use the metallic foil in the laminated film as a single electrical component which comprises a section of an electrical circuit having a separate reference potential to the battery.
The plate-shaped battery of the present invention disposes an island created by a metallic foil comprising a laminated film in proximity to the terminal sealing the positive and the negative terminals.
In such a way, wiring resistance can be minimized and it is possible to make use of a conventionally wasteful space at the sealing section of the electrode terminal of the battery.
The plate-shaped battery of the present invention forms an electrical circuit by mounting one or more than one electrical component on the island of the terminal section.
By such a way, an electrical circuit may be formed which mounts condensers, resistors, PTCs or the like by effectively using a conventionally wasteful space at the sealing section of the electrode terminal of the battery.
The plate-shaped battery of the present invention connects a section of the electrical circuit with the metallic foil in the laminated film, the positive or the negative pole.
In such a way, an electrical circuit such as a protection network for the battery can be formed by effectively using a conventionally wasteful space at the sealing section of the electrode terminal of the battery.
The plate-shaped battery of the present invention disposes a printed board mounting an electrical circuit between a negative or positive terminal and a metallic terminal which is connected electrically with the metal foil in the laminated film and fixes the board onto the terminal sealing laminate.
In such a way, the reliability of the printed board with respect to vibrations or the like may be improved by fixing the printed board with an adhesive or the like to the battery.
The electronic apparatus of the present invention is provided with a plate-shaped battery laminating a polymer resin and a metallic foil and covering a battery core. The plate-shaped battery has a laminated film which seals the positive and negative terminals and which electrically connects the metallic foil with the positive or negative pole of the electrodes. The apparatus also comprises an electrical circuit which mounts one or more than one electrical component on an island created by the metallic foil formed in proximity to the terminal sealing the positive and negative electrode terminals. The plate-shaped battery and the electrical circuit are contained by the main housing and the back housing. By such an arrangement, the plate-shaped battery is fixed with a plate which is comprised by a material composed of at least one of glass, metal or resin. The plate fixes the plate-shaped battery by maintaining a fixed distance with the metallic foil and fixing a condenser capacity. This is achieved by disposition between the metallic foil and the housing mounting a battery core or a plate-shaped battery or a plate fixing the plate-shaped battery or a combination of the two.
In such a way, a fixed distance is maintained between a metallic foil in a laminated section and a plate which fixes a plate-shaped battery or between a board on which a battery core or a plate-shaped battery are fixed or a combination of the above. Thus the capacitance with the battery core is fixed and it is possible to use the capacitance as a section of the circuit.
An electronic apparatus of the present invention fixes the above structure by pressing the plate-shaped battery with a back of the main housing.
In such a way, it is possible to fix the condenser capacity as discussed above in a simple manner and to apply this to a section of the electrical circuit.
An electronic apparatus of the present invention comprises an antenna of a radio device created by a condenser capacity between the reference potential of the radio device supplied by the plate-shaped battery and the metallic foil in the laminated film, and a section or the entirely of the metallic foil.
In such a way, it is possible to use the metallic foil in the laminated film as an antenna and to form a matching circuit by using the condenser capacity between the metallic foil and the earth as a matching condenser in the matching circuit in the electrical circuit.
An electronic apparatus of the present invention fixes the plate-shaped battery to a fixed position in order to maintain a fixed distance between the metallic foil in the laminated film and the earthing or power source line on the printed board.
In such a way, it is possible to maintain the capacitance as discussed above at a normally fixed value in spite of the battery expanding or contracting in response to being charged or discharging electrical power.
An electronic apparatus of the present invention mounts a first connector on an extended tip section, a tip of an electrical wiring which is connected to the cell electrode or a section of the electrical wiring. The extended tip section extends a cell electrode comprising the positive and negative electrode terminals of the plate-shaped battery mounted on the back housing. A connecting device containing a second connector is mounted on an electrical signal line containing the power source circuit of the electrical circuit in the main housing. A circuit electrically connected with the first connector is adhered and connected to the back housing.
In such a way, it is possible to secure an electrical connection of an electrical circuit of an electronic apparatus main body such as a mobile telephone and a battery having a mechanically weak electrode.
The electronic apparatus of the present invention fixes a plate-shaped battery by sandwiching a battery housing, which is a section of the back housing, and the cell electrode of the plate-shaped battery with a fixing means such as a biasing spring or a fixing clip onto the printed board or the housing of another electronic apparatus.
In such a way, it is possible to fix and accurately determine the position of an electrode or a battery by application of a fixing means such as a fixing clip or a biasing spring. Furthermore, it is possible to suppress a contact resistance between the electrode and the wiring to an extremely low level.
The plate-shaped battery of the present invention forms a terminal sealing the positive and negative electrode terminals by thermal fusion of the aforementioned polymer resin on the side of a battery cell without the use of a different resin from the polymer resin. The resin acts as an adhesive with the laminated film when the battery core is covered with the laminated film which has a laminated structure sandwiching a metallic foil with the polymer resin.
In such a way, it is possible to seal the laminated film with a simple structure.
The plate-shaped battery of the present invention adapts the terminal sealed with a laminate film of the positive and negative electrode lead lines which are respectively electrically connected to the positive and negative terminals. The invention is characterized in that a hole is opened in the positive or negative electrode lead lines, a flat net structure or a roughened structure is formed on the surface of the positive or negative electrode lead lines, or the positive or negative electrode lead lines are formed in a branched or zigzag pattern.
In such a way, the adhesive qualities of the laminated film and the positive and negative electrode lead lines are improved and it is possible to reduce horizontal slip and improve strength with respect to detachment of the lead line.
The laminated film in the plate-shaped battery of the present invention comprises a laminated structure of a metallic foil formed from stainless steel and a polymer resin with the polymer resin being disposed on the side of the battery cell.
In such a way, since it is possible to extend a metallic foil made from the stainless steel thinly with few pinholes and with high mechanical strength, it is possible to prevent damage from the exterior from reaching the battery core in comparison with the use of a metallic foil made from aluminum. Furthermore such a film is resistant to corrosion and may be extended thinly, it is possible to reduce the weight of the battery.